Search
Search Results
-
Monitoring temperature patterns at selected world heritage sites in Egypt using high resolution WorldClim data
42-58Views:476Long term temperature patterns helps in assessing changes in the climatic conditions of an area and climatic changes poses a major challenge to the world heritage sites whether it is natural or cultural. Therefore in this study using maximum and minimum temperature data for the period 1960-2021 downloaded from WorldClim 2.1 calculation of mean temperature is done in QGIS environment for the selected UNESCO world heritage sites of Arab Republic of Egypt. WorldClim 2.1 provides finer resolution gridded data downscaled from Climate Research Unit. Trend analysis using linear regression and Mann-Kendall method and Sen’s Slope estimate is used to understand the patterns of mean temperature at all the selected sites. The study reveals that mean temperature at all the selected sites is increasing but since 1990 the sites which are located geographically in lower Egypt are witnessing rapid increase in mean temperature compared to the sites located in upper Egypt which historically witnessed more temperature due to its geographical milieu. This study can help in stimulating the utility of geospatial data in understanding the changes in climatic parameters in relation to world heritage sites. Moreover it can serve as foundation upon which detailed longitudinal site specific investigation can be done.
-
Analysis of Climate Variability and Agricultural Productivity in Mizoram, Northeast India
53-64Views:275Mountainous regions are considered highly vulnerable to the affects of climate change. The extent of change and variability of climatic parameters is still unexamined in many remote mountainous areas. This paper aims in understanding the change in pattern of rainfall and temperature for a period of 30 years in Mizoram. The analysis of time series changing trend in climatic variables is carried out by using Coefficient of Variation (CV), Mann-Kendall (M-K) and Sen’s Slope estimator. The analysis reveals that high variation is observed for both the variables in all the decadal, three decadal and seasonal change. The CV analysis shows that the highest seasonal rainfall variation occurs during winter and the highest seasonal temperature variation occurs during spring. Mann-Kendall test shows a significant change in rainfall with November showing the highest negative trend of rainfall. The temperature trend analysis in the study also reveals drastic change of temperature. An understanding of climatic change, trend and variability helps in predicting for better natural resources from the susceptibility of climate change.
-
Spatial and temporal pattern of soil pH and Eh and their impact on solute iron content in a wetland (Transdanubia, Hungary)
34-45Views:48Land mosaics have direct and indirect influence on chemical reaction and redox condition of soils. The present paper deals with the relationship between some environmental factors (such as soil and vegetation patterns, micro-relief, water regime, temperature and incident solar radiation) and the pH, Eh of soils and solute iron in a headwater wetland in Transdanubia, Hungary. Measurements have been taken in four different patches and along their boundaries: sedge (Carex vulpina, Carex riparia, three patches and two species), horsetail (Equisetum arvense), common nettle (Urtica dioica). The spatial pattern of the studied parameters are influenced by the water regime, micro-topography, climatic conditions and by direct and indirect effects of vegetation. The indirect effect can be the shading, which has influence on soil temperature and on the incident solar radiation (PAR). Root respiration and excretion of organic acids appear as direct effects.. There have been measured individual pH and Eh characteristic in the studied patches. Soil Eh, pH and solute iron have shown seasonal dynamics. Higher redox potentials (increasingly oxidative conditions) and higher pH values were measured between late autumn and early spring. The increasing physiological activity of plants causes lower pH and Eh and it leads to higher spatial differences. Although temperature is an essential determining factor for Eh and pH, but our results suggest it rather has indirect effects through plants on wetlands.
-
Reduction of environmental impacts of heat pump usage with special regard on systems with borehole heat exchangers
66-77Views:72Ground coupled heat pump systems are suitable for extracting subsurface thermal energy with low environmental impact especially regarding CO2 emission. The efficiency of such systems strongly depends on the temperature of the ambient heat (thus underground substrate). This temperature usually changes unfavourably during operation and efficiency becomes lower than the nominal value. Appropriate installation and operation cause lower temperature drop, thus higher efficiency. Consequently, it means lower electricity demand, therefore lower specific CO2 emission, more CO2 saving and lower operation costs. Quantitative analysis with 21 heat extraction models presented in the paper points out that the differences could be significant (up to 30 %), in addition using bivalent mode the environmental impact of the installation or/and operation can be reduced as well, especially using biomass firing as auxiliary heating.
-
In-flight icing characteristics of unmanned aerial vechicles during special atmospheric condition over the Carpathian-basin
74-80Views:49The in-flight aerial icing phenomena is very important for the Unmanned Aerial Vehicles (UAV) because it causes some serious problems such as reduced lift and increased drag forces, significantly decreased angle of attack, increased weight, structural imbalances and improper radio communications. In order to increase flight safety of UAV’s we develop an integrated meteorological support system for the UAV pilots, mission controllers and decision makers, too. In our paper we show the in-flight structural icing estimation method as a part of this support system based on a simple 2D ice accretion model predictions. We point out the role of the ambient air temperature, cloud liquid water content, airfoil geometry and mainly the true airspeed in the icing process on the wings of UAVs. With the help of our model we made an estimation of geometry and amount of ice accretion on the wing of a short-range and a high-altitude and long-endurance UAVs during a hypothetical flight under a typical icy weather situation with St clouds over the Carpathian-basin (a cold-pool situation case study). Finally we point out that our icing estimation system can easily be adapted for supporting the missions of UAVs.
-
Geo-physical attributes of Shushunia’s aquifer, Chhatna block, Bankura district, West Bengal, India
1-11Views:80Shushunia hill lies in a transitional zone of the South Singbhum Mobile Craton and northern Gondwana formation. The Shushunia hill appears like a porcupine peak and it has structural similarity to the Eastern Ghat. The Shushunia hill zone is an example of a contact spring. In the foothill zone, two perennial springs are observed. The study purely deals with its aquifer and water quality. Based on the present rock strata and the nature of the contact aquifer, its early condition has been assumed. The discharge of the confined aquifers occurs by leakage. The water temperature depicts the springs are not of geothermal origin. Shushunia's aquifer is the shallow flow system water table and it is the subdued replica of surface topography. The comparatively high discharge rate during post-monsoon indicates the fractured conduit-water seepage towards the aquifer. Moreover, twin-contact aquifers do not yield water uniformly. The perennial aquifer may act as a municipal water supply source for drinking purposes in the future.
-
Climate as a risk factor for tourism
113-125Views:148Weather and climate risk factors for tourism are surveyed and illustrated with regard to the expected climate changes in Hungary. These changes are not at all advantageous and which affect the business in question both directly and indirectly. These are the summer resort tourism (characterised by bioclimatic indices). Green tourism is the next one to characterise, including skiing, mountain climbing and eco-tourism, as well. Here both day-to-day weather extremes and long-lasting effects on the biota (e.g. drought, or inundation for plain-area eco-tourism). Last, but not least the urban (cultural- and shopping-) tourism is presented, since the large towns exhibit their special climate and different risks. The paper intends to specify these meteorological factors and effects also in terms of the different types of touristic activities. The general statements on the effect of weather and climate on tourism are illustrated by a few individual parameters and also by the so called Physiologically Equivalent Temperature. Annual and diurnal course of this parameter are presented, together with various trends in this variable at different sites and in different (hot and cold) extremities of the occurring values. Other examples, helping the tourism industry are presented in various climate conditions of the country. They include high precipitation and high relative humidity information. The paper also lists the possible adaptation measures to extreme events and also their likely changes in time.
-
Evaluation of climatic conditions from 1978 to 2020 of Oued Souf valley (Southern East of Algeria)
1-10Views:59In this research, a climatic synthesis was built to assess the climatic parameters of the Oued Souf Valley through the meteorological data obtained from Guemar station (airport). It was revealed that the hydrological year of Oued Souf Valley is branded by the presence of a dry period and the total absence of a wet period over the year, even during January, when it was observed to have the lowest temperature and highest precipitation, which classified it as a Saharan climate (Hyper arid). The irregularity and the scarcity of precipitation, high temperatures and extremely high evapotranspiration had significant repercussions on surface runoff and infiltration which implies a high pressure on the water resources of Oued Souf valley and may disrupt the future socioeconomic project and increase the damage of natural drought and desertification.
-
Relation of meteorological elements and air pollutants to respiratory diseases
1-15Views:48This paper determines the characteristic weather types over the Carpathian Basin for the summer – early autumn period (July 15 – October 15) and the winter months (December, January, and February), with the levels of chemical (CO, NO, NO2 , NO2/NO, O3, O3max, SO2, PM10) and biological [Ambrosia (ragweed) pollen] air pollutants, and with their effect to the respiratory diseases. Based on the ECMWF data set, daily sea-level pressure fields analysed at 00 UTC (Coordinated Universal Time) were prepared for each weather type (cluster) in order to detect the relation between, on the one hand, the sea-level pressure patterns and, on the other, the levels of the chemical and biological air pollutants as well as the frequency of the respiratory diseases in Szeged. Objective definition of the characteristic weather types occurred by using the methods of Factor Analysis and Cluster Analysis. As a result, in the summer – early autumn period the total patient number is proportional to the mean monthly temperature, the maximum and minimum temperatures; however, respiratory diseases occur more frequently, when relative humidity is low. On the other hand, in the winter months there is no relation between the meteorological variables and the patient numbers.
-
Is desertification a problem in Hungary?
242-247Views:214The term of “desertification” refers to a land degradation processes of arid, semiarid and sub-humid areas. Although the concept originates from Sub-Saharan Africa, desertification threatens also the area of Hungary. The greatest desertification risk is in the central part of the country, in the Danube-Tisza Interfluve where drought has always been a huge problem for the local society. Aridification processes are mainly due to climate change. Temperature increase and precipitation decrease as well as the increase of the frequency and amplitude of extreme events contribute to the acceleration of desertification risk. Severe or moderate droughts occur in Hungary nearly every year. Drought frequency has increased, primarily in the last decades. Main findings of several research projects of MEDALUS II and III EU Framework projects (experiments on the effects of climate change on vegetation, soils and ground water level) are summarized in the paper.